(a) Technical Field of the Invention
The present invention relates to a reel for releasing or assembling of cable, in particular, to a single-pull, power and signal cable reel which could precisely control the length of the required cable used in PC or related products.
(b) Brief Description of the Prior Art
Conventional reels available in the market include reels employed steel beads as the positioning structure. A loop spring is mounted within the cable-rotating disc to provide the power to restore or retract the lead wire. The positioning structure employs the beads to slidably position the lead wire. In order to allow the positioning by the beads, the bottom section of the cable-rotating disc is provided with mechanical rail, allowing the beads to roll in the rail so as to provide engagement or disengagement.
This type of positioning structure is generally for use in small size reel, and it is employed in smaller size signal transmission cable. This type of reel cannot be used in common type of power cable. Further, under the requirement of a single-pull action on the lead wire, the reel for such cable is not practical and can never be achieved. The drawbacks of the conventional reels are as follows:
(1) The beads need to be within the rail in order to provide engagement and disengagement, and therefore, the engagement and disengagement of beads with the rail will cause the gap of the rail to increase. Subsequently, when the gap is enlarged, the bead may be dislocated, and the reel is not functioning efficiently.
(2) The large gap of the rail will cause noise. Thus, the quality of the reel is poor after a period of application.
(3) When the gap of the rail has been enlarged due to long period of application, besides the noise and the engagement problem of the reel, the operation of the reel will not be reliable.
(4) In this type of reel, the end terminal of the lead must have a spare wire to allow the lead being pulled without affecting the power connection end. The extra length of the spare wire increases the cost of production of the reel. Further, the spare wire may entangle in the course of retraction. Thus, the operation of the conventional reel is not efficient.
Accordingly, it is an object of the present invention to provide a single-pull power and signal cable reel which mitigates the drawbacks mentioned above.